Lithium battery energy storage power station fire protection monitoring and early warning method based on PACK-level two-fluid fire protection

Abstract

The invention discloses a lithium battery energy storage power station fire protection monitoring and early warning method based on PACK-level two-fluid fire protection, belongs to the technical field of energy storage battery safety, and realizes comprehensive efficiency improvement through multi-level cooperative operation. According to the monitoring level, a cluster-level hydrogen sensor is used for capturing a thermal runaway early signal, complementary monitoring is formed in cooperation with a cabin-level multi-type sensor, accurate positioning and early warning of a fault pack are achieved while sensor configuration is simplified, and therefore invalid monitoring and potential safety hazards are reduced. A pack-level double-fluid system is innovatively adopted in the fire-fighting level, the synergistic effect of gas and water is combined, the fire extinguishing efficiency and equipment protection are both considered, and the limitation of a traditional single fire extinguishing mode is avoided; and meanwhile, a cluster-level and cabin-level grading fire-fighting mechanism is constructed, corresponding equipment is started according to early warning level differentiation, and excessive consumption of a fire extinguishing agent and scrapping loss of normal batteries are reduced. In addition, through dynamic monitoring and closed-loop control in the fire fighting process, it is ensured that fire extinguishing treatment is thorough and not excessive.

Description

Technical Field

[0001] This invention relates to the field of energy storage battery safety technology, specifically to a fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire suppression. Background Technology

[0002] New energy storage is a crucial component of my country's new energy security strategy. It plays a significant role in balancing grid load and enhancing the absorption capacity of renewable energy, ensuring grid stability and reducing energy costs. Currently, lithium-ion battery storage holds a dominant position in the new energy storage field. To ensure high energy density while achieving integration, modularity, and rapid deployment, lithium-ion battery storage is primarily containerized. However, in practical applications, lithium-ion batteries pose a risk of thermal runaway due to factors such as overcharging, short circuits, impacts, and manufacturing defects. This thermal runaway can rapidly spread within the sealed container, leading to larger-scale thermal runaway and ultimately causing fires and explosions. Therefore, safety early warning and fire prevention for energy storage power stations are currently hot research areas.

[0003] Currently, thermal runaway monitoring, early warning, and fire protection in lithium battery energy storage power stations have formed multi-level and multi-parameter solutions. For example, in monitoring and early warning, some solutions monitor runaway characteristic signals such as temperature, current, voltage, combustible gas, and smoke at the cabin, cluster, and pack levels. When the monitoring data reaches a preset threshold, the system will issue an alarm signal and perform power outage and fire protection. However, this approach has certain shortcomings. Its monitoring signals are too redundant, the system design is too complex, and the excessive number of sensors occupy a large amount of space in the cabin, which also significantly increases hardware costs and maintenance difficulty. In addition, the electrical sparks generated by the sensors may become the first ignition source in thermal runaway, endangering equipment safety. In terms of fire protection, some solutions employ PACK-level fine water mist spraying and combined chamber-level perfluorohexanone spraying to form a multi-layered protection system. However, due to insufficient monitoring and early warning sensitivity, they cannot respond and fire in time when thermal runaway occurs, leading to the spread of thermal runaway. This requires extensive coverage with extinguishing agents, which wastes extinguishing agents and may cause secondary damage (such as electrical insulation failure). It also results in the scrapping of a large number of high-performance batteries after being sprayed with extinguishing agents, causing significant economic losses. Therefore, a fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire protection is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire protection, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire suppression, comprising the following steps: S1. Sensor signal sampling: Collect characteristic gas concentration signals and temperature signals through sensors arranged inside the lithium battery energy storage power station; S2, Sensor signal feedback: After S1 collects the characteristic gas concentration signal and temperature signal inside the lithium battery energy storage power station, it determines whether the value exceeds the specified threshold, and activates the cluster-level warning or the cabin-level warning according to the different judgments, thus serving as the signal to start the fire protection system. S3. Activate the fire protection system: Based on the warning signal of S2, activate the cluster-level warning or the compartment-level warning respectively, thereby controlling the activation of fire protection equipment at different levels to carry out fire protection operations. S4. Shut down the fire suppression system: During S3, continuously collect sensor signals inside the lithium battery energy storage power station. When the temperature signal or characteristic gas concentration signal is lower than the threshold, shut down the corresponding fire suppression procedure.

[0006] As a further preferred embodiment of this technical solution: In S1, the sensors arranged inside the lithium battery energy storage power station include a hydrogen sensor, a four-in-one sensor, a smoke sensor, and a cabin temperature sensor. Among them, the four-in-one sensor is used to simultaneously monitor the concentrations of four gases, H2, CO, CH4, and C2H2, in the lithium battery energy storage power station.

[0007] As a further preferred embodiment of this technical solution: a hydrogen sensor is installed above each battery pack to collect the hydrogen concentration signal generated by the thermal runaway of the battery pack. A four-in-one sensor is installed on the top of the energy storage cabinet; A smoke sensor, installed at the top of the energy storage cabinet, is used to collect the concentration signal of smoke throughout the lithium battery energy storage power station. Cabin-level temperature sensors are evenly installed on the top of the energy storage power station to collect temperature signals throughout the entire lithium battery energy storage power station.

[0008] As a further preferred embodiment of this technical solution: in S2, the sensor signal feedback includes two types of judgments, namely cluster-level thermal runaway early warning and cabin-level thermal runaway early warning; Among them, when the hydrogen sensor concentration signal exceeds the set threshold, a cluster-level thermal runaway early warning will be issued; When the value of any one of the three types of sensors—the four-in-one sensor, the smoke sensor, and the cabin temperature sensor—exceeds the threshold, a cabin thermal runaway warning will be issued.

[0009] As a further preferred embodiment of this technical solution: in S3, different fire protection systems are activated and corresponding fire protection equipment is turned on according to different warning signals in S2; When a cluster-level thermal runaway warning signal is received, the pack-level fire suppression system is activated, and the corresponding air intake solenoid valve, water intake solenoid valve, and exhaust fan at the cluster level are opened. When a cabin-level thermal runaway warning signal is received, the cabin-level fire suppression system and the pack-level fire suppression system of each cluster level are activated, and the air intake solenoid valve, water intake solenoid valve, exhaust fan, and sprinkler pipe water intake solenoid valve of each cluster level are opened.

[0010] As a further preferred embodiment of this technical solution: in S4, corresponding stop conditions are set according to different fire protection systems; For a pack-level fire protection system in operation, when the temperature sensor value inside the pack is lower than the set threshold, the fire protection is considered to be over and the pack-level fire protection system is shut down. For a compartment-level fire suppression system in operation, when the values ​​of the four-in-one sensor, smoke sensor, and compartment-level temperature sensor are all below the set threshold, the fire suppression is terminated and the compartment-level fire suppression system is shut down.

[0011] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention, through a cluster-level hydrogen early warning + pack-level dual-fluid fire suppression + cabin-level early warning and fire suppression system, achieves early warning and fire suppression of thermal runaway in energy storage power stations while reducing the use of monitoring sensors and saving fire extinguishing agents, thus ensuring the safety of energy storage equipment; 2. In this invention, by arranging a cluster-level hydrogen sensor array, accurate early warning can be achieved through changes in hydrogen concentration in the early stage of thermal runaway of lithium batteries. Compared with the existing technology that relies on redundant monitoring of multiple parameters such as temperature and smoke, this invention reduces the number of sensors and the space occupied in the cabin, reduces hardware costs and maintenance difficulty, and avoids the safety hazards caused by sensor electrical sparks, thus advancing the early warning response time to the early stage of thermal runaway. 3. This invention, through the design of a pack-level dual-fluid fire suppression system, can accurately spray a mixture of water and carbon dioxide (or other gases) onto the thermal runaway PACK unit after the hydrogen sensor triggers an early warning. Compared with the traditional perfluorohexanone total flooding fire suppression method, this invention can greatly reduce the amount of extinguishing agent used, avoid secondary damage such as electrical insulation failure, and at the same time protect unaffected battery packs from extinguishing agent spraying. In a single container scenario, it can effectively reduce battery scrapping losses and significantly improve fire protection economy. 4. This invention constructs a multi-level collaborative operation of cluster-level early warning, pack-level fire protection, and compartment-level early warning and fire protection. It not only achieves early and accurate handling of thermal runaway, but also forms backup protection through compartment-level sensor arrays and sprinkler systems. When cluster-level fire protection fails, the compartment-level system can intervene in time to prevent large-scale spread of thermal runaway. Compared with the single-level fire protection strategy in the prior art, this solution greatly reduces the probability of thermal runaway spread. At the same time, through the flexible selection of dual-fluid extinguishing agents (such as nitrogen and water, heptafluoropropane, etc.), it can adapt to the fire protection needs of different scenarios and improve the system's adaptability. Attached Figure Description

[0012] Figure 1 This is a flowchart illustrating the operation of the fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire suppression, as described in this invention. Figure 2 This is an operational architecture diagram of the fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire protection, as described in this invention. Detailed Implementation

[0013] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Example

[0014] Please see Figures 1-2 This invention provides a technical solution: a fire monitoring and early warning method for lithium battery energy storage power stations based on PACK-level dual-fluid fire suppression, comprising the following steps: S1. Sensor signal sampling: Collect characteristic gas concentration signals and temperature signals through sensors arranged inside the lithium battery energy storage power station; S2, Sensor signal feedback: After S1 collects the characteristic gas concentration signal and temperature signal inside the lithium battery energy storage power station, it determines whether the value exceeds the specified threshold, and activates the cluster-level warning or the cabin-level warning according to the different judgments, thus serving as the signal to start the fire protection system. S3. Activate the fire protection system: Based on the warning signal of S2, activate the cluster-level warning or the compartment-level warning respectively, thereby controlling the activation of fire protection equipment at different levels to carry out fire protection operations. S4. Shut down the fire suppression system: During S3, continuously collect sensor signals inside the lithium battery energy storage power station. When the temperature signal or characteristic gas concentration signal is lower than the threshold, shut down the corresponding fire suppression procedure.

[0015] In this embodiment, specifically: in S1, the sensors arranged inside the lithium battery energy storage power station include a hydrogen sensor, a four-in-one sensor, a smoke sensor, and a cabin temperature sensor. Among them, the four-in-one sensor is used to simultaneously monitor the concentration of four gases in the lithium battery energy storage power station: H2 (hydrogen), CO (carbon monoxide), CH4 (methane), and C2H2 (acetylene). These four gases are key "characteristic products" in the thermal runaway process of lithium batteries.

[0016] In this embodiment, specifically: H2 (hydrogen) is a gas that is generated in the early stage of thermal runaway of lithium battery (SEI film decomposition stage), which can help verify the early warning signal of cluster-level hydrogen sensor; CO (carbon monoxide), CH4 (methane), and C2H2 (acetylene) are gases released during the middle and later stages of thermal runaway in lithium batteries (decomposition of cathode materials and combustion of electrolyte). Their concentrations increase as the degree of thermal runaway intensifies, thus directly reflecting the spread and severity of thermal runaway within the chamber.

[0017] In this embodiment, specifically: a hydrogen sensor is installed above each battery pack to collect the hydrogen concentration signal generated by the thermal runaway of the battery pack; A four-in-one sensor is installed on the top of the energy storage cabinet; A smoke sensor, installed at the top of the energy storage cabinet, is used to collect the concentration signal of smoke throughout the lithium battery energy storage power station. Cabin-level temperature sensors are evenly installed on the top of the energy storage power station to collect temperature signals throughout the entire lithium battery energy storage power station.

[0018] In this embodiment, specifically: in S2, the sensor signal feedback includes two types of judgments, namely cluster-level thermal runaway warning and cabin-level thermal runaway warning; Among them, when the hydrogen sensor concentration signal exceeds the set threshold, a cluster-level thermal runaway early warning will be issued; When the value of any one of the three types of sensors—the four-in-one sensor, the smoke sensor, and the cabin temperature sensor—exceeds the threshold, a cabin thermal runaway warning will be issued.

[0019] In this embodiment, specifically: in S3, different fire protection systems are activated and corresponding fire protection equipment is turned on according to different warning signals in S2; When a cluster-level thermal runaway warning signal is received, the pack-level fire suppression system is activated, and the corresponding air intake solenoid valve, water intake solenoid valve, and exhaust fan at the cluster level are opened. When a cabin-level thermal runaway warning signal is received, the cabin-level fire suppression system and the pack-level fire suppression system of each cluster level are activated, and the air intake solenoid valve, water intake solenoid valve, exhaust fan, and sprinkler pipe water intake solenoid valve of each cluster level are opened.

[0020] In this embodiment, specifically: in S4, corresponding stop conditions are set according to different fire protection systems; For a pack-level fire protection system in operation, when the temperature sensor value inside the pack is lower than the set threshold, the fire protection is considered to be over and the pack-level fire protection system is shut down. For a compartment-level fire suppression system in operation, when the values ​​of the four-in-one sensor, smoke sensor, and compartment-level temperature sensor are all below the set threshold, the fire suppression is terminated and the compartment-level fire suppression system is shut down.

[0021] Working principle: Sensor signal sampling (multi-faceted data acquisition) By precisely deploying four types of sensors in the lithium battery energy storage power station, characteristic signals reflecting the battery status are collected simultaneously, providing a data basis for subsequent early warning. Sensor signal feedback (tiered early warning judgment) The collected characteristic gas concentration, temperature, and smoke signals are compared with thresholds. Based on the signal source and the type of exceedance, two types of tiered early warnings are triggered, which serve as the core basis for the activation of the fire protection system. This means cluster-level thermal runaway early warning. Only when the concentration signal collected by the hydrogen sensor above a certain battery pack exceeds a set threshold is it determined that the battery pack has entered an early thermal runaway state and a cluster-level early warning is triggered. The cabin-level thermal runaway warning is triggered when the value of any one of the three sensors—the four-in-one sensor, the smoke sensor, and the cabin-level temperature sensor—exceeds the corresponding threshold (e.g., the four-in-one sensor shows an excessive level of a certain type of gas, smoke concentration, or cabin temperature). This indicates that the thermal runaway has spread to the cabin level and triggers the cabin-level warning. Activate the fire protection system (tiered equipment linkage). Based on the warning level, activate different levels of fire protection systems and link dual-fluid (gas and water) fire protection equipment to achieve precise fire control and avoid over-response. Corresponding cluster-level early warning: Only activate the PACK-level fire protection system of the cluster, and simultaneously open the corresponding air inlet solenoid valve (to introduce fire extinguishing gas), water inlet solenoid valve (to introduce fire extinguishing water) and exhaust fan (to expel toxic gas) for localized treatment of the thermal runaway point of a single cluster; Corresponding cabin-level early warning: Simultaneously activate the cabin-level fire protection system and all cluster-level PACK-level fire protection systems. That is, in addition to opening the air inlet solenoid valve, water inlet solenoid valve, and exhaust fan of each cluster, the water inlet solenoid valve of the sprinkler pipe is also opened. Through the synergy of cabin-level sprinklers and cluster-level air and water, the spread of thermal runaway within the cabin is comprehensively suppressed. The fire protection system is shut down (dynamic monitoring closed loop). During fire protection operations, corresponding sensor signals are continuously collected, and differentiated stop conditions are set according to the fire protection level to ensure that the system is accurately shut down after the fire protection effect is achieved, thus avoiding waste of resources.

[0022] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lithium battery energy storage power station fire monitoring and early warning method based on PACK-level two-fluid fire extinguishing, characterized in that, The method comprises the following steps: S1, sensor signal sampling: collecting characteristic gas concentration signals and temperature signals through sensors arranged inside the lithium battery energy storage power station; S2, sensor signal feedback: after collecting the characteristic gas concentration signals and temperature signals inside the lithium battery energy storage power station through S1, it is judged whether the values exceed the specified threshold, and different cluster level early warning or cabin level early warning is started according to the judgment, so as to serve as the signal for starting the fire extinguishing system; S3, starting the fire extinguishing system: according to the early warning signal of S2, the cluster level early warning or the cabin level early warning is started respectively, so as to control the start of different levels of fire extinguishing equipment for fire extinguishing operation; S4, closing the fire extinguishing system: during the process of S3, the sensor signals inside the lithium battery energy storage power station are continuously collected, and when the temperature signal or the characteristic gas concentration signal is lower than the threshold, the corresponding fire extinguishing program is closed.

2. The PACK-based two-fluid fire-fighting lithium battery energy storage power station fire-fighting monitoring and early warning method according to claim 1, characterized in that: In S1, the sensors arranged inside the lithium battery energy storage power station include a hydrogen sensor, a four-in-one sensor, a smoke sensor and a cabin level temperature sensor; The four-in-one sensor is used to synchronously monitor the concentrations of H2, CO, CH4 and C2H2 in the lithium battery energy storage power station. 3.The PACK-based two-fluid fire extinguishing lithium battery energy storage power station fire monitoring and early warning method according to claim 2, characterized in that: The hydrogen sensor is installed above each cluster of battery packs; The four-in-one sensor is installed at the top end of the energy storage cabinet; The smoke sensor is installed at the top end of the energy storage cabinet; The cabin level temperature sensor is uniformly installed at the top of the energy storage power station.

4. The PACK-based two-fluid fire-fighting lithium battery energy storage power station fire-fighting monitoring and early warning method according to claim 3, characterized in that: In S2, the sensor signal feedback includes two kinds of judgments, namely cluster level thermal runaway early warning and cabin level thermal runaway early warning; When the hydrogen sensor concentration signal exceeds the set threshold, the cluster level thermal runaway early warning is performed; When any one of the four-in-one sensor, the smoke sensor and the cabin level temperature sensor exceeds the threshold, the cabin level thermal runaway early warning is performed.

5. The PACK-level two-fluid fire extinguishing based lithium battery energy storage power station fire monitoring and early warning method according to claim 1, characterized in that: In S3, different fire extinguishing systems are started according to different early warning signals in S2, and the corresponding fire extinguishing equipment is opened; When the cluster level thermal runaway early warning signal is received, the pack level fire extinguishing system is started, and the cluster level corresponding air inlet pipe electromagnetic valve, water inlet pipe electromagnetic valve and exhaust fan are opened; When the cabin level thermal runaway early warning signal is received, the cabin level fire extinguishing system and the pack level fire extinguishing system of each cluster level are started, and the air inlet pipe electromagnetic valve, the water inlet pipe electromagnetic valve, the exhaust fan and the spray pipe water inlet pipe electromagnetic valve of each cluster level are opened.

6. The PACK-level two-fluid fire-fighting based lithium battery energy storage power station fire-fighting monitoring and early warning method according to claim 1, characterized in that: In S4, the corresponding stop conditions are set according to different fire extinguishing systems; When the temperature sensor value in the pack is less than the set threshold, the pack level fire extinguishing system is considered to be extinguished, and the pack level fire extinguishing system is closed; When the values of the four-in-one sensor, the smoke sensor and the cabin level temperature sensor are all less than the set threshold, the cabin level fire extinguishing system is considered to be extinguished, and the cabin level fire extinguishing system is closed.

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